Electrode for geophysical surveys



May 23, 1933. M. Mama-ma am y y ELECTRODE FOR GEOPHYSICAL SURVEYS Filed Jan. 9, 1929 Patented May 23, 1933 UNITED STATES PATENT OFFICE HAGNE KORTENSON, Ol TBONDHJ'EM, NOB-WAY "Emerson: ron onormrsrcar. scams Application filed January 9,1929, Serial No. 881,258, and in Norway January 12, 1828.

It is previously known that several ore- Fig. 4 shows a diagram of connections containing rocks have electric potentials for a measuring apparatus. which can be utilized for the purpose of find- In the drawing, Fig. 1, 1 is aperforated ing or locating the ore. cylindrical hollow metal core, the upper end One of the main difliculties, when underof which is closed by means of a cork or the taking such survey, is ,to prevent that the like 2. The porous container 3 encircles the electrodes which are used for connecting the lower part of the metal core, while its upper measuring-apparatus to the ground, become part is covered by some insulating material 4. polarized. It has been tried to remedy this In Fig, 2 th container is shown, consistdifficulty by using electrodes, consisting of a ing of 9, material, hose porosity decreases metal rod in a porous cylinder, said cylinder through it nti ro s ti being filled with a salt solution containing In Fig. 3 the container consists of two sepasaid metal. rate parts, of which the outside one has in- The present invention relates to electrod creasing porosity towards the outside, while 15 of this class, and lts P P ls l p an the inside one has increasing porosity in the electrode, the construction of Wl'llCh comprises th di ti several advantages TGSPBCILJ lZO lJhQ Etlii-n arrangement as gbgve described ready knQWn ".lP f l ctrodes. preferably he used for given types of meas- One ob ect of this invention is to provide unwell-Gs,

an electrode Wher the metallic Core is F The porous material can he manufactured roundfld by a Porous contamel', poroslly from a number of diiierent materials, among of Whlch 111 steps l y deci'eases which may he mentioned clay, carhorundum, the metal core to the outslde of the Q f plaster of Paris, and other solid electrolytes Preferably the metalhc consists it or halt-conducting materials. The decrees r hollow perforated metal cylinder, filled with 5mg respectivly w increasing pmosity apsaturated Salt. Solutlon of the same mew} the container may he obtained for instance (Ior example Zmc 9 copper) Very d by building the container from layers or: results may be Obtamed when hygroscopic grainy material with difi erently sized grains. used These layers may he loosely packed together e porous contzlmer can be .made m l or separated by means of separating walls Piece of the same f of i l consist of some porous material, or the grains of the of seyeral pieces of difierent materials. separate layeps may be m y toggthgfu Wlth Such cqnstltlctlon the @moum of for instance Toy means of adding special electrolyte per cubic unit volume will decrease Ditch b burning 85 the container from the inside to i A The principal use of the alcove described side; at the same time the electrode will have y w gi i h i l Surveys i g a mechanically Solid construction eral, but they can alsh he used for other purh details 0f II B H I 0f the Elecposes, for instance in electrolytical processes. 40 trodes ll f r e be varied to a great l/Vhen using these electrodes for electrical tent, depending on its field of application. measurements, as for instance in connection The invention is illustrated in the annexed with electrical ore-searching, any previously drawing as an example only. known method can he used.

' Fig. 1 is a View, diagrammatically illus- For loest results, the measuring instrutrating an electrode, adapted for ore survey ments which are heing used, should not exaccording to the invention. tract any energy from the field between the Fig, 2 is a section through a broken-away electrodes. 7 piece of the porous container. @ne instrument which is used and which Fig. 3 is a view similar to Fig. 2, but of a to some extent will fulfill this requirement, is

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modified embodiment of the invention. the compensating potentiometer. But even 9 l a compensating lnstrument requ1res some current when being adjusted. For this reason, this type of instrument is not without influence on the polarization.

A measuring apparatus which will work without consumption of energy can be constructed by; using one or more steps of audion-tube-voltmeters, where the grid of the first tube is given a proper negative potential to prevent any grid current from flow- %n Fig. 4 is shown a diagram-connection for an audion voltmeter of t is type.

In this figure A represents a switch, whose terminals 5 and 6 by means of proper connections are connected to electrodes, which can be grounded.

B represents a potentiometer, ada ted to control the electric energy from the attery G (1.5 volt) in such a manner that the grid in the audion'tube D will be given a proper ne ative potential.

a and C, are rheostats, adapted to re latethe filament current through D and ,E is the anode resistance for connecting the second tube D,. F is the grid battery.

The anode batteries are connected at 7 and 8, the potential is volts. At 9 the filament battery is connected with a potential of 4.5 volts.

I claim 1. An electrode for. electrical measurements or the like comprising a porous container, the porosity of which decreases from the interior towards the exterior, a solution of a metal salt in said container, and a metal membermounted in said solution.

2. An electrode for. electrical measurements or the like comprising a porous container, the porosity of which decreases from the interior towards the exterior, the said porous container consisting of at least one solid electrolyte formedof material which has a depolarizing efiect on the electrodes, a solution of metal salt contained in said container, and a metal part comprising a perforated cylinder mounted in said container and adapted to be filled with the said solution.

3. An electrode for electrical measure ments or the like comprising a porous containerconsisting of at least one solid electrolyte arranged in such manner that the porosity thereof is at a minimum at a point within the container wall and increases gradually towards the surfaces of the said wall, a solution of a metal salt contained in said container, and a metal part comprising a perforated cylinder mounted in said container and adapted to be filled with the said solution.

4. Electrode for electrical measurements and other purposes, especially for geo-physical survey, consisting of a metal part, surrounded by a porous container or the like, which contains a solution of a metal salt, the porosity of said containerdecreasing from the inside towards the outside, thereb eliminating potentials due to polarization y preventing the appearance of uneven changes in the electrolyte concentration within-the electrode.

5. Electrode for electrical measurements and other purposes, especially for geo-physical surve s, consisting of a metal part, surrounded y a porous container or the like, containing a solution of a metal salt, said metal part consisting of a perforated cylinder, ada ted to be filled with the electrolyte, and sai porous container consisting of one or more solid electrolytes, the porosity of said container decreasin from the inside towards the outside, there eliminating potentials due to polarization by preventing the appearance of uneven changes in the electrolyte concentration within the electrode.

6. Electrode for electrical measurements and other purposes, especially for geo-physical surveys, consisting of a metal part, surrounded by a porous container or the like, containing a solution of a metal salt, said metal part consisting of a erforated cylinder, adapted to be filled wit the electrolyte, and said porous container consisting of one or more solid electrolytes, the porosity of said container decreasing from the inside towards some point within the container wall, from where the porosity will increase towards the outside surface, thereby eliminating potentials due to polarization by preventing the appearance of uneven changes in the electrolyte concentration within the electrode.

7 The combination of anelectrode for electrical measurements, and other purposes, especially for geo-physical survey, consisting of a metal part, surrounded by a porous container or the like, which contains a solution of a metal salt, the porosity of said container decreasing from the inside towards the outside, thereby eliminating potentials due to polarization by preventing the appearance of uneven changes in the electrolyte concentration within the electrode, with a measuring system, comprising an audion-tube, and connections for separately connecting either of the electrodes of a source of grid bias to the grid of the audion so that there will be no direct connection between the electrodes.

8. A measuring system comprising electrodes for electrical measurements for geophysical survey, consisting of a metal part, surrounded by a porous container or the like, which contains a solution of a metal salt, the porosity of said container decreasing from the inside towards the outside, audion-tubes,

and connections for separately connectin either of the electrodes or a source of gri bias to the grid of the first audion, to influence the passage of current through the tubes in such a way that no current can flow from one electrode directly to another, all for the purpose of providing a system where polarization of the electrodes will not take place.

9. A measuring system comprism electrodes for elctrical measurements an other purposes, especially for geo-physical survey, consisting of a-metal part, surrounded by a porous container or the like, containing a solution of a metal salt, said metal part consisting of a perforated cylinder, adapted to be filled with the elctrolyte, and said porous container consisting of one or more solid electrolytes, the porosity of said container decreasing from the inside towards the outside, audion-tubes, and connections for separately connecting either of the electrodes or a source of grid bias to the grid of the first audion to influence the passage of current through the tubes in such a way that no current can flow from one elctrode directly to another, all for 2 the purpose of providing a system where polarization of the electrodes will not take place.

10. A measuring system, comprising electrodes for electrical measurements and other 2 purposes, especially for geo-physical survey, consisting of a metal part, surrounded by a porous container or the like, containing a solution of a metal salt, said metal part consisting of a perforated cylinder, adapted to be filled with the electrolyte, and said porous container consisting of one or more solid electrolytes, the porosity of said container decreasing from the inside towards some point within the container wall, from where the porosity will increase towards the outside surface, audion-tubes, and connections for separately connecting either of the electrodes or a source ofgrid bias to the grid of the first audion, to influence the passage of current through the tubes in such a way that no current can fl-ow from one electrode directly to another, all for the purpose of providing a system, where polarization of the electrodes will not take place.

In testimony whereof I have signed my name unto this specification.

- MAGNE MORTENSON. 

